Patients with chronic obstructive pulmonary disease (COPD) are at increased risk for venous thromboembolism (VTE). We analyzed a large Spanish database to determine the incidence of VTE in these patients during hospitalization. A retrospective chart review of cohort of consecutive patients admitted with COPD as the primary reason for discharge in Spain between January 1st 2006 and December 31st 2007 was performed. For each patient, demographic data, risk factors for VTE and the diagnosis of VTE during hospitalization was recorded. We analyzed the clinical data of 313,233 adults with acute exacerbations of COPD admitted to the hospital at any public centre in Spain, in 2006 and 2007. We identify 3,562 new diagnosed VTE events among 270,840 COPD patients hospitalized more than two days (incidence 1.32%). Hospitalized-acquired VTE risk factors were male gender (odds ratio [OR] 1.77; CI95% 1.66-1.90), neoplasic disease (OR 2.93 CI95% 2.69-3.16, systemic arterial disease (OR 1.17 CI95% 1.10-1.36), decubitus ulcer (OR 1.19 CI95% 1.01-1.43), diabetes (OR 0.74 IC95% 0.69-0.81), and atrial fibrillation (OR 0.79 CI95% 0.72-0.87). VTE appears as a major threat to patients admitted for acute exacerbation of COPD, and pharmacologic prophylaxis should be considered in all high risk situations.